R. Chmelarova et al., PROTECTIVE EFFECT OF HEXETIDINE AGAINST IN-VITRO BACTERIAL DEMINERALIZATION OF BOVINE ENAMEL AND DENTIN IN THE PRESENCE OF FLUORIDE, Caries research, 31(6), 1997, pp. 457-462
Bovine enamel and dentin specimens were overlaid with acidogenic Strep
tococcus mutans suspensions in agarose. In this model, the minimal dem
ineralisation-inhibiting concentration (MDIC) of hexetidine was determ
ined in the presence of fluoride. A commercially available mouthwash c
ontaining 0.1% (2.9 mmol/l) hexetidine was diluted serially and added
to the bacterial suspensions together with 0, 5.3, or 26.3 mu mol/l fl
uoride (NaF). After 22 h of incubation at 37 degrees C the bacterial s
uspensions were removed and assessed for calcium and lactate. The resu
lts showed significant inhibitory effects of hexetidine on the deminer
alisation of the enamel specimens with a MDIC between 15 and 31 mu mol
/l hexetidine. In the presence of fluoride, approximately fourfold hig
her concentrations of hexetidine were needed for a significant additio
nal protection of the enamel. No synergistic effect between hexetidine
and fluoride was observed. For the demineralisation of the dentin spe
cimens, the MDIC of hexetidine had a value between 31 and 61 mu mol/l.
At both these concentrations the dentin specimens were relatively les
s protected in the presence than in the absence of fluoride, and some
synergistic effect between hexeditine and fluoride was observed.